Natural porous media, such as subterranean reservoirs containing hydrocarbons, are typically highly heterogeneous and complex geological formations. While recent advances, specifically in characterization and data integration, have provided for increasingly detailed reservoir models, classical simulation techniques tend to lack the capability to honor all of the fine-scale detail of these structures. Various methods and techniques have been developed to deal with this resolution gap.
The use of upscaling has particularly been employed to allow for computational tractability by coarsening the fine-scale resolution of the models. Upscaling of multiphase flow in porous media is highly complex due to the difficulty of delineating the effects of heterogeneous permeability distribution and multi-phase flow parameters and variables. Because the displacement process of multi-phase flow in porous media shows a strong dependency on process and boundary conditions, construction of a general coarse-grid model that can be applied for multi-phase flow with various operational conditions has previously been hampered.